Several years ago, I scratch built a 14 inch turntable for my DC layout (DC at the time). It is purely manual, no automatic drive or anything, nor any electronics. It has the typical split ring rail for plus and minus power when turned. What do I need to do (if anything) to make this compatible for DCC. It IS a "turning" track. I intend to keep it manual ("armstrong", or in this case "fingerstrong"!). Can I just bring DCC power to it as it is, or is there something that I should do to make it work in DCC? What happens when I turn the bridge across the split ring rails? a short? It has been working great in DC. Is it not necessary to have the split ring rail in DCC? Appreciate any suggestions.
Thanks. Al
With a split ring pickup you have do do NOTHING for DCC< since that will reverse the polarity for you.
The downside is, if the gaps are big enough that the pickup wheels don;t span them, then you might have sound dropouts if turning a loco with a soudn decoder. For DCC you don;t need a split ring, just two wipers of some sort, either a contrinuous rail plus a wiper on the shaft, or two wipers on the shaft, and use an autoreverser to flip the polarity.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I use copper wipers on the bridge for pick-up, and a .25 in. phono plug for the shaft which has contacts that I don't use....feeder wires go directly to the split rails.
Are you saying that I could connect the split rails (continuous rail) for DCC? or just leave them as they are. I have the splits 180 degrees from the lead track, as well as the diverging tracks so as not to be over the splits during loco movements. If I don't need to change it, that would be fine with me! I'd like to avoid having to use an auto reverser if possible.
-Al
As is, with a split rail - is there an actual gap at the two splits, or is it a gap in the sense that the rails are cut through? Reason for this question is if it is just a narrow gap like you'd make for a rail gap elsewhere, the pickup wheels on the turntable bridge will bridge them as it rotates and this will cause a short. It works on DC because (hopefully!) the power is off to the bridge track while the turntable is moving. With DCC, the power is always on.
If you can make the gaps wide enough without too much trouble, then you can simply feed DCC to the two sections of ring rail, and it will work fine. Except as I noted, because of the dead section, if you have sound locos, the sound will cut out and restart any time you spin the loco 180 degrees.
To avoid the sound cutout, you would have to switch to the other power option of using the wipers on the plug, and connectign a DCC autoreverser. It's not difficult, two wires in and two wires out to the turntable. Nothign fancy is needed, and they are usually self-powered so the 4 wires are all there is. The Digitrax AR-1 works well and is simple to set up, and is not expensive. Works with any DCC system, there's absolutely nothing in the unit specific to Digitrax.
astapleford I use copper wipers on the bridge for pick-up, and a .25 in. phono plug for the shaft which has contacts that I don't use....feeder wires go directly to the split rails. -Al
I too have a scratch-built 'finger strong' turntable using a quarter inch phone plug for the center pivot. I connected the bridge rails (Track) to the phone plug. Then I used an auto-reverser connected between the phone socket and the main DCC bus. Piece of cake and it works like a charm.
I think that if you can change it easily to use the phone plug and an auto reverser, you should do it. If you can't, cut two more gaps in the ring rail to make two isolated sections for your pick-ups to cross without shorting.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.